Pumping device for a lubricant of an internal-combustion engine

ABSTRACT

A pumping device suitable for a lubricant of an internal-combustion engine, for example, of the piston construction, includes a pressure pump device and a suction pump device, which suction pump device has several suction pumps which are connected with suction devices of the internal-combustion engine. In order to improve the pumping device with respect to its function and construction, adjacent suction pumps are constructed as gear pumps connected to the suction device, the gears of the gear pumps being arranged coaxial with respect to one another and being connected with one another by a driving device.

BACKGROUND AND SUMMARY OF THE INVENTION

[0001] This application claims the priority of Application No. 101 39 267.2, filed Aug. 9, 2001 in Germany, the disclosure of which is expressly incorporated by reference herein.

[0002] The present invention relates to a pumping device for a lubricant of an internal-combustion engine, for example, of the piston type.

[0003] A known pumping device, as in French Patent Document FR 848 159, for the lubricant circulation in an internal-combustion engine has a pressure pump device and a suction pump device. The suction pump device is formed by several suction pumps which are spaced with respect to one another and are arranged at different suction points of the internal-combustion engine. This reference contains no information concerning the construction of the suction pumps and the method of their drive.

[0004] It is therefore an object of the present invention to provide a pumping device for a lubricant of an internal-combustion engine which is distinguished by a good functioning and a simple construction.

[0005] The principal advantages achieved by means of the invention are that the pumping device comprises highly effective suction pumps constructed as gear pumps which, because they have identically constructed components, contribute to a cost-effective construction. In this case, each gear pump is connected with mutually separate suction points of the internal-combustion engine. In addition, the gear pump equipped with two mutually meshing gears has two mutually separate chambers accommodated in a housing of the gear pump, which chambers are connected to the above-mentioned suction points. These chambers are separated by a partition which extends at a right angle with respect to the center axes of the gears. The partition is inserted as a flat disk into axial grooves of the gears and interacts in a sealing manner with an interior wall of the housing. Finally, the partition is constructed in the manner of spectacles consisting of two parts which are joined in a longitudinal center plane including both center axes of the gears.

[0006] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The drawings show an embodiment of the invention in which:

[0008]FIG. 1 is a partial longitudinal sectional view of a pumping device for a lubricant of an internal-combustion engine;

[0009]FIG. 2 is a sectional view according to Line II-II of FIG. 1; and

[0010]FIG. 3 is a sectional view according to Line III-III of FIG. 1.

DETAILED DESCRIPTION OF THE DRAWINGS

[0011] Only a portion of a crankcase 2 on which a pumping device is provided is outlined of an internal-combustion engine 1 of the piston type which is not shown in detail. The pumping device comprises a pressure pump device, which is not shown, and a suction pump device 3 by means of which the circulation of the lubricant in the internal-combustion engine is ensured. The pressure pump device is arranged on a first longitudinal side and the suction pump device 3 is arranged on a second longitudinal side 4 of the crankcase 2. The suction pump device 3 is formed by at least two suction pumps 5, 6 which are connected with suction devices 7, 8 of the internal-combustion engine.

[0012] The suction pumps 5, 6 are constructed as gear pumps 9, 10 which each have two mutually meshing gears 11, 12 and 13, 14 and are arranged side-by-side such that the gears 11 and 13 of the gear pumps 9, 10 are aligned coaxially with respect to one another and interact by means of a driving device 15. Each gear pump, for example, 9, has a housing 16 of an approximately oval shape which is provided with housing covers 19, 20 on faces 17, 18. The gears 11, 12 are disposed in the housing covers 19, 20, in which case the housing 16, the housing covers 19, 20 and the gears 11, 12 and 13, 14 of both gear pumps 9, 10 are essentially identically constructed parts. The driving device 15 is a shaft 21 which is in an operative connection with the gears 11 and 13 of the adjacent gear pumps 9, 10. At its ends 22, 23, the shaft 21 has external toothings 24,25, which external toothings 24, 25 interact with internal toothings 26 and 27 of the gears 11 and 13.

[0013] In order to implement a suctioning of the crank chamber and a suctioning of the adjacent points in the internal-combustion engine 1, each gear pump, for example, 10, is connected with separate suction points 28 and 29 of the suction device 8, as can be seen in FIG. 1. For this purpose, two separate chambers 30 and 31 are provided in the housing 16, which chambers 30 and 31 are connected to the suction points 28 and 29 and in which the gears 13, 14 of the gear pump 10 operate. The chambers 30 and 31 in the housing 16 are separated by a partition 32 which extends at a right angle with respect to the center axes 33 and 34 of the gears 13, 14. The partition 32 is constructed as a flat disk and is inserted into grooves 35 and 36 of the gears 13, 14, the free ends 37 and 38 of the partition 32 sealingly interacting with interior wall sections 39 and 40 of the housing 16. Finally, the partition 32 is constructed in the manner of spectacles, as can be seen in FIG. 2, and consists of symmetrical parts 41, 42 which are joined in a longitudinal center plane A-A including the two center axes 33 and 34 of the gears 13, 14.

[0014] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. 

What is claimed is:
 1. A pumping device for a lubricant of an internal-combustion engine, comprising a pressure pump device and a suction pump device, which suction pump device has several suction pumps which are connected with suction devices of the internal-combustion engine, wherein adjacent suction pumps are constructed as gear pumps connected to the suction devices, and wherein adjacent gears of adjacent gear pumps are arranged coaxial to one another and are connected with one another by means of a driving device.
 2. The pumping device according to claim 1, wherein the gear pumps essentially comprise identically constructed parts.
 3. The pumping device according to claim 2, wherein the identically constructed parts of the gear pumps are formed by the gears, a housing and a housing cover.
 4. The pumping device according to claim 1, wherein the driving device is a shaft which is in an operative connection with the gears of the gear pumps.
 5. The pumping device according to claim 4, wherein the shaft has external toothings at ends thereof and wherein the external toothings interact with internal toothings of the gears of the gear pumps.
 6. The pumping device according to claim 1, wherein each gear pump is connected with mutually separate suction points of a respective suction device of the internal-combustion engine.
 7. The pumping device according to claim 6, wherein each gear pump has two gears arranged parallel to one another and operating in a housing, and wherein the two gears operate in the housing in mutually separate chambers which are connected to the mutually separate suction points of the internal-combustion engine.
 8. The pumping device according to claim 7, wherein the mutually separate chambers are separated by a partition which extends at a right angle with respect to center axes of the two gears.
 9. The pumping device according to claim 8, wherein the partition is constructed as a flat disk and is inserted into grooves of the two gears and, by way of free ends of the partition, the partition sealingly interacts with interior wall sections of the housing.
 10. The pumping device according to claim 9, wherein the partition is constructed in a manner of spectacles and consists of two parts, which are joined in a longitudinal center plane including the center axes of the gears.
 11. A suction pump device for a lubricant of an internal-combustion engine, comprising: a first suction pump having a first and a second gear; a second suction pump having a first and a second gear; wherein the first gear of the first suction pump is arranged coaxially with the first gear of the second suction pump; and a driving device in operative connection with the first gear of the first suction pump and the first gear of the second suction pump.
 12. The suction pump device of claim 11, wherein the driving device is comprised of a shaft with external teeth at opposing ends thereof, and wherein the external teeth engage with internal teeth of the first gear of the first suction pump and internal teeth of the first gear of the second suction pump, respectively.
 13. The suction pump device of claim 11, wherein the first suction pump is disposed in a first housing and wherein the second suction pump is disposed in a second housing. 